The saturation magnetization of a ferromagnetic film is determined by the total vector sum of magnetic moments per iron atoms included in the ferromagnetic film. The magnetic moment per iron atom of a pure stable iron is about 2.2 .mu..sub.B (Bohr magneton) which is increasable when the interatomic distance of the pure stable iron, in other words lattice constant thereof, is increased. One known method of increasing the interatomic distance is effected to force to dissolve nitrogen atoms in solid state into the pure stable iron. The other known method is to grow iron on a simple metal which has a larger interatomic distance than iron and to increase the interatomic distance at the interface thereof as disclosed, for example, in C. L. Fu, J. Freeman, and T. Oguchi "Prediction of Strongly Enhanced Two-Dimensional Ferromagnetic Moments on Metallic Overlayers, Interfaces, and Superlattices" (PHYSICAL REVIEW LETTERS, volume 54, Number 25, pp 2700-2703), wherein an increase of magnetic moment per iron atom is predicted by growing iron on Copper (Cu), Silver (Ag) an Gold (Au) which have a larger interatomic distance than that of iron. However since Copper, Silver and Gold are non-ferromagnetic metals, a saturation magnetization of the combined film in total comprising a lamination of Copper, Silver or Gold layers and iron layers decreases below that of an iron film alone.